diff --git a/content/learn/03.programming/06.memory-guide/memory-guide.md b/content/learn/03.programming/06.memory-guide/memory-guide.md
index bed73b18b0..9ca2889dd2 100644
--- a/content/learn/03.programming/06.memory-guide/memory-guide.md
+++ b/content/learn/03.programming/06.memory-guide/memory-guide.md
@@ -411,7 +411,7 @@ The following table shows basic value data types in Arduino:
| **Type** | **Byte Length** | **Range of Values** |
|:---------------:|:---------------:|:-------------------------------:|
| `boolean` | 1 | Limited to logic true and false |
-| `char` | 1 | -128 to 128 |
+| `char` | 1 | -128 to 127 |
| `unsigned char` | 1 | 0 to 255 |
| `byte` | 1 | o to 255 |
| `int` | 2 | -32,768 to 32,767 |
@@ -447,4 +447,4 @@ Memory architectures in microcontroller-based systems is a pretty vast topic; if
[1] S. F. Barrett and D. J. Pack, Microchip AVR® Microcontroller Primer: Programming and Interfacing, Third Edition (Synthesis Lectures on Digital Circuits and Systems), Morgan & Claypool, 2019.
[2] J. Y. Yiu, The Definitive Guide to ARM Cortex -M0 and Cortex-M0+ Processors, Second ed., Newnes, 2015.
-[3] J. Yiu, The Definitive Guide to ARM® Cortex®-M3 and Cortex®-M4 Processors, Third ed., Newnes, 2014.
\ No newline at end of file
+[3] J. Yiu, The Definitive Guide to ARM® Cortex®-M3 and Cortex®-M4 Processors, Third ed., Newnes, 2014.